Add comprehensive unit tests for uncovered areas

[Copilot]

Summary

Adds 10 new unit-test files (1,216 lines) covering previously uncovered areas in both v1 and v2 APIs. All tests are pure unit tests — no database required — and focus on edge cases, error paths, and fallback behaviour.

What’s new

File	Scope	Key coverage
tests/v1/test_unit/test_enums_and_exceptions.py	v1 enums & exceptions	OrderByDirections, FKNotFoundError, AlreadyExistsError, NotFoundError
tests/v1/test_unit/test_schemas_base.py	v1 schemas	normalize_datetime_to_utc, utc_datetime_encoder, datetime_encoder, PaginationMetaSchema, AdminMeta, ClientMeta, Filter, OrderBy, OrFilterGroup
tests/v1/test_unit/test_utils.py	utilities	now_without_tz, validate_exclusive_presence (including falsy-but-not-None edge cases)
tests/v2/test_unit/test_exceptions.py	v2 exceptions	FKNotFoundError, AlreadyExistsError, NotFoundError
tests/v2/test_unit/test_factory.py	factories	build_repository, build_service, build_service_for_repo — standard & soft-delete variants, custom classes, config propagation, error paths
tests/v2/test_unit/test_payload_mixin.py	payload mixin	_dump_payload with dict and Pydantic-model inputs, exclude_unset behaviour
tests/v2/test_unit/test_query_dsl_tokens.py	query DSL	parse_filter_token, parse_sort_token, apply_filter_operator, resolve_to_column, build_filter_clauses, build_sort_clauses, build_query_params — all operators, error paths, predicate fields, empty-token handling
tests/v2/test_unit/test_schemas_base.py	v2 schemas	ClientMeta, PaginationMetaSchema.calculate (negative-total clamping)
tests/v2/test_unit/test_serializer_mixin.py	serializer mixin	serialize_one, serialize_many — explicit schema arg, fallback to detail_schema / list_schema, empty-list handling, prefer_list_schema flag
tests/v2/test_unit/test_updated_by_mixin.py	updated-by mixin	_apply_updated_by — actor_id injection, preservation of existing value, missing-attribute error, custom attribute name

Fixes applied

1. Soft-delete factory tests — added _SoftWidget(SoftDeletableModel) so SoftDeleteRepository.__init__ succeeds (models must expose deleted_at).
2. Query-DSL rendering — replaced str(col) with _render(col) (PostgreSQL dialect + literal binds) for deterministic assertions.
3. Mypy strict-mode compliance — cast resolve_to_column results to ColumnElement[Any] before passing to _render.
4. Additional fix — added missing Any type parameter to ColumnElement casts in test_query_dsl_tokens.py to satisfy mypy strict = true.

Coverage impact

Metric	Before	After
Total	~84 %	90 %
src/notora/utils/validation.py	partial	100 %
src/notora/v1/exceptions/common.py	partial	100 %
src/notora/v1/schemas/base.py	partial	99 %
src/notora/v2/exceptions/common.py	partial	100 %
src/notora/v2/repositories/query_dsl.py	partial	95 %
src/notora/v2/services/mixins/updated_by.py	partial	100 %
src/notora/v2/services/mixins/payload.py	partial	100 %
src/notora/v2/services/mixins/serializer.py	partial	100 %

Verification

• make lint passes (ruff, mypy, pyright, stubtest)
• make test passes (345 tests)
• No breaking changes to public API

Follow-up ideas (out of scope)

• v2/enums/* is still at 0 % direct coverage — tiny import-level tests could be added.
• v2/services/mixins/m2m.py has several uncovered branches (bulk-attach edge cases, rollback paths).
• v1/persistence/repos/base.py and v1/services/base.py remain at ~70 %; full coverage would require heavy mocking of SQLAlchemy sessions.

[Pentusha]

Overall Assessment

Approve with minor nits. This is a solid, well-structured test PR that meaningfully increases coverage (+6 pp) without touching production code. The tests are focused, fast, and exercise edge cases effectively.

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Highlights

• Good separation of concerns. Each test file maps cleanly to a single module or mixin.
• Edge-case coverage. test_utils.py correctly tests falsy-but-not-None values (0, "", []). test_serializer_mixin.py covers empty lists, schema overrides, and fallback chains.
• Factory tests are thorough. test_factory.py validates not just happy paths but also the TypeError raised when a soft-delete service class is paired with a non-soft-delete repo.
• Query-DSL tests are comprehensive. All nine filter operators, sort directions, predicate fields, and error paths are covered. Using PostgreSQL dialect compilation with literal binds makes assertions deterministic.
• No database required. All new tests are pure unit tests, keeping the feedback loop fast.

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Minor Issues / Nits

1. ColumnElement type-arg consistency

test_query_dsl_tokens.py already casts to ColumnElement[Any] in two places (fixed in this PR), but the _render helper itself is typed as ColumnElement without a parameter:

def _render(clause: ColumnElement) -> str:  # type: ignore[type-arg]

Consider aligning it with ColumnElement[Any] and removing the # type: ignore[type-arg] for consistency.

2. v2/enums still uncovered

src/notora/v2/enums/__init__.py and src/notora/v2/enums/base.py remain at 0 % coverage. They are tiny (6 lines total), so a single test file importing and asserting OrderByDirections.ASC.value == "asc" would bring them to 100 % with minimal effort.

3. _make_obj helper in test_serializer_mixin.py

Using types.SimpleNamespace() is clever for from_attributes=True schemas, but it’s worth adding a short comment explaining why it works (no required SQLAlchemy-mapped fields), so future readers don’t assume it’s a general-purpose model mock.

4. Exception test duplication

tests/v1/test_unit/test_enums_and_exceptions.py and tests/v2/test_unit/test_exceptions.py share nearly identical assertions for FKNotFoundError, AlreadyExistsError, and NotFoundError. This is expected because the classes are duplicated across versions, but if the project ever deduplicates them, both files will need updating.

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Suggestions for Follow-up PRs

1. Cover m2m mixin branches — src/notora/v2/services/mixins/m2m.py has several uncovered rollback / bulk-attach paths.
2. Cover v2/enums — trivial 6-line win.
3. Property-based tests — hypothesis is already in the lockfile (via README.md reference). A few property-based tests for PaginationMetaSchema.calculate or validate_exclusive_presence could catch boundary bugs automatically.

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Checklist Verification

Check	Status
Lint (ruff, mypy, pyright, stubtest)	✅ Pass
Tests (345/345)	✅ Pass
No production-code changes	✅ Confirmed
Coverage increase	✅ 84 % → 90 %

[Copilot]

Pull request overview

Adds broad unit-test coverage for previously under-tested v1/v2 helpers, schemas, exceptions, factories, and service mixins, plus a small typing cleanup in pytest fixtures. This strengthens confidence in core library behavior without changing production APIs.

Changes:

• Adds new v1 unit tests for enums, exceptions, schema helpers, pagination metadata, and validation/time utilities.
• Adds new v2 unit tests for exceptions, factories, query DSL token parsing/building, payload/serializer/updated-by mixins, and base schemas.
• Cleans up pytest fixture typing and updates an existing query-schema test helper for deterministic SQL rendering.

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
tests/v2/test_unit/test_updated_by_mixin.py	Adds unit coverage for UpdatedByServiceMixin payload injection and error paths.
tests/v2/test_unit/test_serializer_mixin.py	Adds serializer mixin tests for schema fallback and error behavior.
tests/v2/test_unit/test_schemas_base.py	Adds v2 schema tests for ClientMeta and pagination total clamping.
tests/v2/test_unit/test_query_dsl_tokens.py	Adds broad query DSL parser/clause-builder coverage.
tests/v2/test_unit/test_pydantic_query_schemas.py	Refactors SQL rendering helper to use a PostgreSQL dialect instance.
tests/v2/test_unit/test_payload_mixin.py	Adds _dump_payload unit tests for dict and Pydantic inputs.
tests/v2/test_unit/test_factory.py	Adds coverage for repository/service factory helpers and soft-delete variants.
tests/v2/test_unit/test_exceptions.py	Adds v2 exception behavior tests.
tests/v2/conftest.py	Adds a concrete type annotation for the fixture request object.
tests/v1/test_unit/test_utils.py	Adds coverage for time and exclusive-presence validation utilities.
tests/v1/test_unit/test_schemas_base.py	Adds v1 schema/helper tests for datetime handling, pagination, filters, and ordering.
tests/v1/test_unit/test_enums_and_exceptions.py	Adds v1 enum and exception tests.
tests/conftest.py	Adds typing to the custom pytest option hook.

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